Electric motors are used in a wide range of industries for converting kinetic energy into electrical energy. Traditional electric generators convert all the kinetic energy received into electric energy for a subsequent use in various applications, regardless of the effective need of electrical energy of these applications and variation thereof through time. Traditional systems comprising electric motors are open loop systems using an input unit of energy to generate an output unit of energy. This generally results in an inefficient use of energy when used in applications having a fluctuation need of energy through time.